Whole grains may benefit a person’s health in a number of ways. For example, by providing a source of fiber and potentially preventing some diseases. However, some people should avoid eating certain whole grains.
Whole grains are cereals and other grains that contain all the natural edible parts of the plant. Compared to refined grains, in which manufacturers have removed some of the nutritional parts.
This article defines whole grains and discusses some of their potential health benefits. It also explores who should avoid eating them.
A note about sex and gender
Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.

The Whole Grain Initiative (WGI) defines whole grains as consisting of the intact, flaked, cracked, ground, or otherwise processed kernel after removing inedible parts, like the husk and hull. The kernel is the seed from which the grain will grow if someone plants it.
Additionally, all the anatomical parts of the grain, including the bran, endosperm, and germ should be present in the same relative proportions as the intact kernel.
The WGI also highlights that when manufacturers label foods as whole grain, they must contain
In the definition of whole grains, the WGI includes cereal grains in the Poaceae grass family and certain pseudocereals. The following are examples of whole grains:
In comparison, manufacturers remove some parts of the grain for taste and appearance to produce refined grains and products, such as white rice and wheat flour.
Nutrition resources
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The Dietary Guidelines for Americans state that
Eating fiber
Whole grains are a good source of fiber.
- wheat
9–27% - oats 10–38%
- barley 10–30%
- rice 3–10%
- buckwheat groats 7–12%
For example, eating a 40 g portion of rolled oats for breakfast contributes just over
A 2022 review indicates that eating whole grains
The review suggests that this may be due to the resistant starch content in whole grains, which does not increase blood sugar and may cause a feeling of fullness, or satiety. The large intestine, which is at the end of the digestive tract, digests resistant starch.
A 2022 review of research suggested that eating whole grains
Studies included in the 2022 review also demonstrated a decreased risk of high blood pressure with increased consumption of dietary fiber.
In addition, whole grains may
A 2020 systematic review and meta-analysis found that whole grain intake was associated with a 6–12% lower risk of total cancer mortality when comparing the highest and lowest intake groups. Additionally, eating 15–90 g of whole grains daily was associated with a 3–20% lower cancer risk.
Additionally, the study found that whole grains may help to prevent the following specific types of cancer:
A 2022 review indicated that studies found that consuming dietary fiber from cereals
Additionally, the review suggested that eating whole grains may help to reduce the risk of developing type 2 diabetes, which occurs as a result of high blood sugar levels rising when the body does not respond to insulin correctly.
People with celiac disease should not eat whole grains that contain gluten. The National Institute of Diabetes and Digestive and Kidney Diseases advises that gluten
- wheat and different types of wheat such as:
- spelt
- emmer
- semolina
- durum
- rye
- triticale, which is a cross between rye and wheat
- barley and barley extracts
In addition, doctors
A person should speak with a healthcare professional to find out if they may benefit from limiting gluten in their diet.
Whole grains may include a range of cereal grains and some pseudocereals, such as wheat and oats.
In addition to providing a person with dietary fiber, some research suggests that whole grains may help to prevent the risk of certain chronic conditions.
However, people with celiac disease should avoid eating whole grains that contain gluten. Additionally, doctors may advise individuals with IBS to avoid grains containing gluten but increase dietary fiber from other whole grains such as rice.